To 150 grams of a 30% solution, 20 grams of water was added. What is the mass fraction in the new solution?

1. Let’s find what mass of salt is in the initial solution:

m (salt) = w (salt) * misk (solution) = 0.3 * 150 = 45 g;

2. calculate the mass of the new solution:

mnov (solution) = mout (solution) + madd (H2O) = 150 + 20 = 170 g;

3.Calculate the mass fraction of salt in the resulting solution:

wnew (salt) = m (salt): mnew (solution) = 45: 170 = 0.2647, or 26.47%.

Answer: 26.47%.